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Topic Review
Molecular Imprinting
Molecular imprinting is a technique for creating artificial recognition sites on polymer matrices that complement the template in terms of size, shape, and spatial arrangement of functional groups. The main advantage of Molecularly Imprinted Polymers (MIP) as the polymer for use with a molecular imprinting technique is that they have high selectivity and affinity for the target molecules used in the molding process. 
  • 2.5K
  • 30 Nov 2021
Topic Review
Biofilm and Pathogen Inhibition in Cooling Towers Using Natural Chemistry
Industrial comfort cooling and process cooling typically employ water evaporative cooling towers (CTs) to dissipate reject heat.  This warm water, enriched with nutrient materials scrubbed from the air or in source water, provides a nurturing environment for a wide variety of neutrophilic microorganisms, some of which are human pathogens.  For example, cases of Legionella pneumophila infection have been traced to CT Systems that have become pubic hazards in recent years.  Typically, one or more toxic microbicides are applied to control the problem.  This article highlights two case studies that utilize ultra-softened (<0.3 mg/L total hardness), highly-concentrated chemical components, naturally present in almost all makeup water sources used by CT Systems, that can generate high-pH, high-TDS cooling water.  At sufficient concentrations, these two natural parameters are hostile to microorganisms, including protozoa and slime-forming (biofilm) bacteria that harbor pathogens.  Field testing for Adenosine Tri-Phosphate (ATP), reported in Relative Light Units (RLU), provides a quick, sensitive method to detect all water-borne microbiological activity present in CT Systems and verifies the effectiveness of the anti-microbial program by quantifiable data, reported as ATP-RLU.
  • 2.5K
  • 28 Oct 2020
Topic Review
Multivariable Formulation of Surfactant-Oil-Water Systems
Surfactant-Oil-Water (SOW) systems are found in nature and synthetic products. They usually result in two immiscible phases, e.g., for two liquids, a water phase (often a brine), and an oily phase (which could be extremely complex as petroleum). Surfactant partitions between the two phases according to some physicochemical rules due to molecular interactions. There is a very particular formulation case in which SOW systems can form three immiscible phases, that is, two excess phases (water and oil) in equilibrium with a  so-called middle phase (because of an intermediate density that places it in the middle of a test tube). This middle phase is a so-called bicontinuous microemulsion which has no droplets dispersed in an external phase as a typical emulsion, but a complex single-phase structure similar to a disordered liquid crystal. When stirred, SOW systems can form multiple dispersed systems that can be described as macroemulsions or nanoemulsions depending on the drop size (O/W or W/O) or multiple emulsions (w/O/W or o/W/O) with droplets inside larger drops. Since the beginnings of the 20th century with Bancroft’s rule, the properties of these systems have been related to many thermodynamic variables, generally with one effect at a time. Nowadays, the generalized physicochemical concept of SOW systems with many formulation variables involved allows to make predictions in various application cases, even for very complex systems, as in enhanced oil recovery (EOR), crude oil dehydration, paints, foods, cosmetics and pharmaceutical formulations, that requires the control on 6-8 variables or even more. This is mainly because of the presence of mixtures of oils from linear alkanes to triglycerides or complex molecules perfumes, or a mixture of salts with cations from sodium to calcium or aluminum, and anions like chloride to phosphate. The complexity is even worse with mixtures of very different surface-active species, resulting in non-linear interactions.
  • 2.5K
  • 17 Aug 2021
Topic Review
Iron Oxide Nanoparticles (IONPs)
The unique physical properties (physical identity) of iron oxide nanoparticles (IONPs), their ample possibilities for surface modifications (synthetic identity), and the complex dynamics of their interaction with biological systems (biological identity) make IONPs a unique and fruitful resource for developing magnetic field-based therapeutic and diagnostic approaches to the treatment of diseases such as cancer. In this entry, we revisited the current knowledge on IONP interaction with cells of the mononuclear phagocytic system (macrophages), dendritic cells (DCs), endothelial cells (ECs), and cancer cells, correlating synthetic identity with the biological effects that IONPs trigger in these cells (biological identity). Furthermore, we thoroughly discuss current understandings of the basic molecular mechanisms and complex interactions that govern IONP biological identity, and how these traits could be used as a stepping stone for future research.
  • 2.4K
  • 28 Oct 2020
Topic Review
Poly (Butylene Succinate) and PBS Copolyesters Degradation
The impact of plastics on the environment can be mitigated by employing biobased and/or biodegradable materials (i.e., bioplastics) instead of the traditional “commodities”. Poly (butylene succinate) (PBS) emerges as one of the most promising alternatives due to its good mechanical, thermal, and barrier properties, making it suitable for use in a wide range of applications. Nevertheless, less information regarding PBS biodegradation is available, as research is still ongoing. PBS degradation methods include hydrolytic degradation, enzymatic degradation, and biodegradation in environmental conditions, such as burial, activated sludge, and compost.
  • 2.4K
  • 22 Mar 2022
Topic Review
Green Tea
Green tea is a type of tea that is made from Camellia sinensis leaves that have not undergone the same withering and oxidation process used to make oolong teas and black teas. Green tea originated in China , but its production and manufacture has spread to many other countries in Asia. Several varieties of green tea exist, which differ substantially based on the variety of C. sinensis used, growing conditions, horticultural methods, production processing, and time of harvest. Although there has been considerable research on the possible health effects of consuming green tea regularly, there is little evidence that drinking green tea has any effects on health.
  • 2.4K
  • 08 Nov 2022
Topic Review
ZnO Photocatalysts for the Treatment of Wastewater
The presence of contaminants in wastewater, surface water, groundwater, and drinking water is a serious threat to human and environmental health. Their toxic effects and resistance towards conventional water treatment methods have compelled the scientific community to search for an environmentally friendly method that could efficiently degrade toxic contaminants. In this regard, visible light active photocatalysts have proved to be efficient in eliminating a wide variety of water toxins. A plethora of research activities have been carried out and significant amounts of funds are spent on the monitoring and removal of water contaminants, but relatively little attention has been paid to the degradation of persistent water pollutants. In this regard, nanoparticles of doped ZnO are preferred options owing to their low recombination rate and excellent photocatalytic and antimicrobial activity under irradiation of solar light. 
  • 2.4K
  • 18 Feb 2022
Topic Review
Sugar Based Surfactants
Sugar-based surfactants are a class of surfactants derived from natural sugars, such as glucose, sucrose, and maltose. These surfactants have gained significant interest in recent years due to their biodegradability, low toxicity, and high compatibility with biological systems. Sugar-based surfactants are classified into two main groups: alkyl polyglucosides (APGs) and saccharide fatty acid esters (SFAEs). APGs are produced by reacting a fatty alcohol with glucose, while SFAEs are produced by esterifying a sugar molecule with a fatty acid. APGs have excellent cleaning and foaming properties and are used in a variety of personal care and household products, including shampoos, body washes, and dishwashing detergents. SFAEs are mainly used in the food industry as emulsifiers and stabilizers. One of the main advantages of sugar-based surfactants is their biodegradability, which means that they break down into harmless substances when exposed to environmental conditions such as sunlight, water, and microorganisms. This makes them an attractive alternative to synthetic surfactants, which can persist in the environment for a long time and have negative impacts on ecosystems.
  • 2.4K
  • 24 Mar 2023
Topic Review
Carbon-based Materials for Hydrogen Storage
Carbon in its various forms (e.g., nanotubes, fullerenes, graphene) create a family of substances that enable the storage of large amounts of hydrogen in a reversible manner, which is confirmed by both computer simulations and experimental results.The main contraindication to using hydrogen as an energy source in mobile applications is still the low gravimetric density achieved by the available systems (according to the recommendations of the US Department of Energy, it should be 6 wt.%).
  • 2.4K
  • 27 May 2021
Topic Review
Ultra-Heat Treatment on Milk Proteins
Milk contains approximately 3.5% by weight protein, which is a highly complex system. This milk protein is usually divided into two main fractions based on their solubility nature. Casein proteins are about 75% to 80% of the total protein in the milk and precipitate at pH 4.6 at 20 °C, while 20% of the protein remains in the serum.
  • 2.4K
  • 07 Oct 2021
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